feat: Update version to 3.0.1 and enhance portal settings configuration

deployment/add-custombranding.ps1

@@ -42,6 +42,11 @@ $classicActionName = 'CustomBranding.Classic.ScriptLink'
 function New-DefaultCustomBrandingConfiguration {
     return @{
         schemaVersion = 2
+        portalSettings = @{
+            providerKey = 'custombranding'
+            contractVersion = 1
+            minimumPortalSettingsVersion = '3.0.0'
+        }
         enabled = $true
         debug = $false
         allowedCssHosts = @()
@@ -122,6 +127,11 @@ try {
     $configuration = Get-ExistingConfiguration -Action $action
 
     $configuration.schemaVersion = 2
+    $configuration.portalSettings = @{
+        providerKey = 'custombranding'
+        contractVersion = 1
+        minimumPortalSettingsVersion = '3.0.0'
+    }
     if (-not $configuration.ContainsKey('placeholdertop')) { $configuration.placeholdertop = @{ elements = @() } }
     if (-not $configuration.ContainsKey('placeholderbottom')) { $configuration.placeholderbottom = @{ elements = @() } }
     if (-not $configuration.ContainsKey('cssfiles')) { $configuration.cssfiles = @() }